Grand Canyon of Yellowstone with waterfall cascading into river below

Yellowstone National Park. Old Faithful Geyser. Clouds of spray and steam with pine forest beyond.

Yellowstone National Park. Mammoth Hot Springs. View over white and yellow sulphur deposits forming waterfall effect

Yellowstone National Park. Geysers at West Thumb.

Hot springs with ashen pool of acid dissolved mud and clay in the foreground

Two Bison crossing a river

Two Bison standing together with one grazing and the other looking toward the camera

Detail of Minerva rock terraces

People looking into Morning Glory hot pool in the National Park. Ochre and turquoise rock